Optometer.



H- SMITH.

OPTOMETER.

APPLIOATION TILED JULY 18, 100B.

91 9 ,481 Patented Apr. 27, 1909.

. I I M1 HORACE SMITH, O1 MONROE, NORTH CAROLINA.

OPTOMETER.

Specification of Letters Patent.

Patented April 27, 1909.

Application .filed July 18, 1908. Sari-a1 No. 444,159.

To all whom it may concern:

Be it known that 1, Homes SMITH, citizen of the United States, residingat Monroe, in the county of Union and State of North Carolina, haveinvented new and useful Improvements in Optometers, of which thefollowing is a specification.

My invention pertains to means for testing the eyes; and it has for itsgeneral object to provide a light, compact and readily portable device,constructed with a view of being attached to and supported by a patientshead, and of being expeditiously and easily adjusted, while sosupported, to enable an oculist or Optician to determine the characterand extent of defects of the eyes.

lVith the foregoing in mind the nature of the invention, and itsnovelty, utility and practical advantages will be fully understood fromthe following description and claims when the same are read inconnection with the drawings accompanying and forming part of thisspecification, in which:

Figure 1 is a perspective view illustrating the device constituting thebest practical embodiment of my invention of which .I am cognizant asthe same appears when relatively arranged to an attaching frame to testthe right eye of a patient. Fig. 2 is a side elevation of my noveldevice as the same appears when removed from the frame illustrated andwhich I prefer to employ.

Similar letters designate corresponding parts in both views of thedrawings, referring to. which:

A is a frame for effecting connection between my novel device and apatients head and utilizing the patients head to support the deviceincidental to adjustment of the movable lens of the latter to determinedefects of vision. The said frame A may be of any construction consonantwith the pur pose of my invention, though I prefer to construct it afterthe manner of the well known trial frame 2'. 6., have it comprise anose-piece or bridge a, temples b, and semi-circular holders 0, ofchannel-form in cross-section, extending between and connecting thenose-piece a and the temples b. I also prefer to provide the frame Awith a removable disk (Z which is opaque and is designed to be seated inone of the holders 0 of the frame while the stationary lens of my noveldevice is seated in the othe'i' holder 0 of the frame, this in order toexclude the light from one of the patients eyes during the testing ofthe other eye. U will be readily understood from this that when thestationary lens of the testing device is positioned in the right handholder c of frame A, the opaque disk (Z will be arranged in the lefthand holder 0 of the frame, and when the stationary lens of the testingdevice is placed in the left hand holder of the frame, the disk (Z willbe placed in the right hand holder thereof.

h Iy novel testing device is illustrated in both figures of thedrawings, and by reference to the drawings it will be understood thatthedevice comprises a body plate l) having a longitudinal slot 0 andalso having on its upper face a suitable scale 7', a fingerpiece fixedto and rising from the body plate B adjacent to the rear end thereof, astationary lens h arranged below and disposed at a right angle to thebody plate and connected with the rear end thereof through the medium ofa metallic or other suitable arm 2', a slide disposed in the slot 0 andhaving portions 7c and Z disposed below and above the body plate,respectively, and also having a fingerpiece m, and a movable lens parranged parallel to the stationary lens h and connected through themedium of an arm 7* with the slide By virtue of this construction itwill be manifest that a person grasping the finger-piece m is enabled toreadily move the lens 7) toward and from the stationary lens h; and itwill also be manifest that the slide j and the lens p will remain in theposition in which they are placed so as to enable the oculist orOptician by observing the pointers s on the slide j and the scale on theupper side of the body plate to ascertain the character and extent of adefect of the eye.

In the practical use of my improvements, the frame A is placed on thepatients head in the same manner as a pair of spectacles, and when it isdesired to subject the right eye to examination, the opaque disk (Z isplaced in the left hand holder (1 of the frame, and the stationary lens72. of the testing device is placed in the right hand holder 0 of theframe. lVith this done a test card is located at a suitable distancefrom the patients head, and the lens 7) is moved to the end of the bodyplate remote from the stationary lens h. The patient is then directed tolook at the test card while the operator gradually slides the lens ptoward the stationary lens h, and when the patient informs the operatorthat all of the letters on the test card are clear to him, the operatorstops the movable lens and by referring to the pointers and the scale isenabled to readily determine the glass best suited to the eye that isbeing tested. hen the left eye of the patient is to be tested, the stationary lens h is placed in the left hand holder 0 of frame A, and theopaque disk (Z is placed in the right hand holder 0, after which theoperation described with reference to the right eye is repeated.

I prefer in practice that one of the lenses employed in my novel devicebe a plus lens and that the other be a minus lens, for then by adjustingone lens with respect to the other and referring to the scale on thebody plate B the operator is enabled to readily determine the dioptricstrength of lens needed for the eye that is being tested.

It will be gathered from the foregoing that the apparatus described is,as a whole, light and compact, and may therefore be produced at smallcost and may be conveniently carried in the pocket or in a small case.

As before stated, the construction herein illustrated and describedconstitutes the best practical embodiment of my invention of which I amcognizant, but it is obvious that in the future practice of theinvention such changes or modifications may be made as fairly fallwithin the scope of my invention as defined in the claims appended.

Having described my invention, what I claim and desire to secure byLetters-Patent, is:

1. In optical testing means, the combination of a body bearing a scale,a plus lens carried by the body, a minus lens also carried by the body;one of the said lenses be ing adjustable toward and from the other andbeing provided with a pointer for cooperating with the scale on thebody, and means for effecting connection between the body and a patientshead to utilize the latter to support the body.

2. In optical testing means, the combination with a frame having anose-piece and holders disposed at opposite sides of the nose-piece; ofan opaque disk adapted to be remot ably arranged in one of the holdersof the frame, and a device comprising a body, a lens fixed with respectto the body and adapted to be removably arranged in one of the holdersof the frame, and a lens arranged parallel to the first named lens andadjustable on the body toward and from said first named lens andprovided with a pointer for cooperating with a scale on the body.

In testimony whereof I have hereunto set my hand in presence of twosubscribing witnesses.

HORACE SMITH.

Vfitnesses H. B. CLARK, N. G. ENGLISH.

